Automatic fuel burner



July 9, 1935. w. A. FOX ET AL 2,007,601

AUTOMATI C FUEL BURNER Filed Sept. 11, 1933 wuumm AFC;

J1 Md George L. po novan Patented July 9, 1 935 "P TENT F Fl Q E AUTOMATIC FUEI; BURNER William A. Fox and George Li: Donovan, Vancouver, British Columbia, Canada, assignors of one-third to Joseph Summerfield, Vancouver, British Columbia, Canada Application September 11, 1933,-Serial No. 683,008

1 Claim. (01-. 110-32)" 'This invention relates to a mechanical fuel "stoker'particularly adapted for use with domestic furnaces on account of its compactness; and simplicity of parts and ease of operation.

Our invention is particularly designed to operate with a minimum of care and attention and be silent in'operation, I

Our invention is designed for efficient operation w'ith a wide range of fuels and to operate successfully whileburning the cheaper grades like slack and broken coals.

An object of our invention has been to provide an economically constructed automatic fuel stoker suitable for use with all kinds of domestic furnaces. V

' A further object of our invention has been to provide a small compact, silent running stoker requiring a minimum of attention to operate.

' Still another object of our invention has been to provide an automatic stoking device suitable for operation with'thermostatic controls.

A still further object of our invention has been to provide a device of this character of few parts, sturdy in construction and not liable to disarrangement and economical to install and operate. a

With these and other objects in view we have inventedthe automatic stoking device which is the subject matter of'this application and which is further illustrated in the accompanying drawing and described in the following specification forming part of this application.

In the accompanying drawing:--

Figure 1 is a diagrammatic illustration of the fuel stoker appliedto an ordinary domestic furnace which is partially indicated.

Figure 2 is an end view of the stoker with the front cover removed to illustrate the positioning of the motor, fan, gear reduction unit and cam, and

Figure 3 is an end view of one of the fire gra-te bars to show the longitudinal corrugations formed in the bottom thereof to comprise air passages.

In the drawing like numerals indicate like parts and the numeral I indicates an automatic fuel stoking device generally connected to a heating furnace 2. A casing or housing 3 is provided in which is mounted the motor 4 driving the fan 5 housed within the fan housing 6.

Intermediate the fan and motor is the pulley 1 driving by the belt 8 the larger pulley 9 mounted upon the end of one of the shafts of the gear reduction unit In. The secondary shaft of the gear reduction unit 10 projects from the opposite side and has the rotatable swash plate cam l I' u mounted thereon, the periphery of which is engaged by the roller cross-head l2 connected by the extension arm 13 with the slidable stoker plate 14.

The 'S'BO-KBI' plate M is positioned within the housing I5 directly below the end of the fuel hopper l6 whereby fuel may be fed directly upon the stoker plam from the hopper Hi.

The stoker plate M has an inclined surface formed upon its upper face to provide the thickened inner end H which acts in the nature of a ram to force the fuel forwardly when the plate I4 is reciprocated by the cam ll.

Intermediate the furnace 2 and hopper I6 is an inspection door' l8 having a right angled draught groove l9 formed therein.

Mounted within an extension grate housing '20 is a series of stationary and movable grate bars 2l-2lx arranged in stepped relation below and beyond the stoker plate 14.

The movable grate bars are connected by the rods 22 to the right angled'bar 23, the opposite end of which isconnected by an adjustable cross arm 24'(-see Figure 2) to the roller cross-head l2 by which reciprocation of the movable grate bars 2| is secured simultaneously with the reciprocation of the stoker plate [4. l

A pair of clamp collars 25 is provided upon the end of the bar 23 by which the stroke of the bar 23 may be adjusted to move said bar a predetermined distance so that the movement of the movable grate bars may be adjusted to suit the rate of combustion of the fuel being used.

The stoker housing 3 is supported upon the outside of the furnace 2 by a pair of adjustable supports 26 which take the major weight of the .fire door is removed and the extension grate housing is inserted therethrough, and the door opening closed around the housing 20, either by a suitable casting or other means. A plastic cement arch of the nature of a crown sheet is built up in the furnace immediately above the grate housing 26 to ensure proper circulation immediately below, after which and assuming the hopper has been filled with suitable fuel, the motor 4 may be started to provide the necessary draught from the fan 5 to support combustion, and also to start the reciprocation of the stoker plate I4 by which fuel is fed and forced over the grate bars 2| from the hopper Hi.

The reciprocation of the stoker plate I 4 progressively feeds fuel from the hopper 5 onto the grate bars 2| while the reciprocation of the movable grates advances the combusting fuel from one step to another until thoroughly burnt and reaches the lowermost grate bar from which the burnt product of combustion is forced oif into the ash-pit below by movement of the movable grate bars.

Having now particularly described our invention what we claim and desire to be protected in by Letters Patent, is:

In a mechanically operated fuel stoking device, the combination with a fuel hopper, a motor housing below the hopper, a motor located in said housing, a fan housing adjacent said motor housing into which the shaft of said motor projects, a fan in said fan housing driven by said motor shaft, the top of said fan housing being opento discharge air beneath the grate bars, a series of alternately arranged stationary and movable grate bars located above the fan housing, a reduction gear unit mounted on and operatively connected with said motor within said motor housing and including an extension shaft, a swash plate cam on said extension shaft, 8. stoker plate mounted within said motor housing and located below said hopper to receive fuel from the hopper and deliver it to the grate bars, a cross head connected with said stoker plate and with said movable grate bars and cooperating with said swash plate cam for actuation of said stoker plate and said movable grate bars, the air from said fan passing between said grate bars substantially as shown and described.

WILLIAM A. FOX. GEORGE L. DONOVAN. 

